<!DOCTYPE html>
<html>
<body>
<div role="list">
  <div role="listitem" aria-label="Item 1"></div>
  <div role="listitem" aria-label="Item 2"></div>
</div>
<script>
  function go() {
    var item3 = document.createElement('div');
    item3.setAttribute('role', 'listitem');
    item3.setAttribute('aria-label', 'Item 3');
    document.querySelector('[role="list"]').appendChild(item3);
  }
</script>
</body>
</html>
